Sensors are used in a wide range of analytical operations to analyze various chemical and biochemical reactions such as nucleic acid sequencing reactions. In many biological and biomedical applications, it is very desirable to have sensors integrated with signal detection devices such as Complementary Metal-Oxide Semiconductor (CMOS) detection circuitry because such integration provides a number of benefits including miniaturization, automated detection, high performance and reduced reagent costs. However, sensors are usually operated in a liquid environment while traditional CMOS circuits are generally designed without concern for contact with aqueous solutions, imposing a great challenge in the development of integration and packaging processes. To make robust and reliable analytical device packages, post-sensor and post-CMOS fabrication and packaging processes must meet the needs of every component of each individual device and the interfaces between different components including biochemistry, fluidics, optics and electronics.
In addition, many analytical operations may benefit from the ability to analyze the reaction of individual molecules or a relatively small numbers of molecules. One approach of monitoring only one or a few molecules at a time is to provide a sensor having different characteristic properties on various different portions of optical confinements. For example, it can be desirable to have different surface properties for portions within the observation regions and outside of the observation regions of the optical confinements. Integration of such sensors with CMOS circuits imposes additional difficulties in the development of packaging processes as these different characteristic properties cannot be degraded or compromised during the integration and packaging.
There is thus a need in the art for analytical device packages and robust and reliable packaging methods to make analytical device packages.
The information disclosed in this Background section is provided solely to provide a general background of the embodiments described herein and is not an acknowledgement or suggestion that this information forms part of the prior art already known to a person skilled in the art.